It may be a given, but how much of the game will you be able to mod, or will modding be limited to additional dreams? I mainly ask because of the gray man, which can appear in multiple dreams. Will you be able to add an entity of a similar nature? I mean, there is that gray dog within the original game files...
Will you be able to add custom text or video dreams? Will custom dreams be able to have additional features present in the base dreams, like static links (in entities or the map itself, say, to other custom dreams or even base dreams), special or rare events (stretching, entities on certain day types, video segments etc.), disabling of entities like the gray man, or certain positions on the dream chart?